201239196 六、發明說明： 【發明所屬之技術領域】 本申請案主張20U年2月9日申請之美國臨時_ 第61/441,027號之權利。 。 上述申請案之完整教示係以引用之方式併入本文中。 【先前技術】 當前可用之低溫泵（不論是用開放低溫循環抑或封閉 低溫循環冷卻）一般遵循相同設計概念。通常在4 K至25 K 之範圍中操作的低溫度第二階段低溫板為主要抽汲表面。 此表面藉由通常在40 Κ至13〇 Κ之溫度範圍中操作之高溫 度輻射屏蔽罩所包圍，該輻射屏蔽罩對較低溫度陣列提供 輻射屏蔽。輻射屏蔽罩一般包含外殼，除了在定位於主要 抽汲表面與待抽空之腔室之間的前低溫板陣列處之外，該 外殼為封閉的。此較高溫度之第一階段前陣列充當用於諸 如水蒸氣之高沸點氣體（稱為第j型氣體）之抽汲位置。 在操作中，諸如水蒸氣之高沸點氣體在前陣列上冷 凝。較低沸點氣體穿過前陣列且進入輻射屏蔽罩内之體積 中。諸如I氣之第π型氣體在第二階I陣列±冷凝。諸如 氫氣、氦氣及氖氣之第ΠΙ型氣體在|具有可感知之蒸 氣壓。為了捕獲第ΠΙ型氣體，可用諸如活性碳、沸石或分 子篩之吸附劑塗佈第二階段陣列之内表面。吸附為氣體藉 以藉由保持在低溫溫度下之材料以實體方式捕獲且藉此自 裒兄移除的過程。隨著氣體因此冷凝或吸附至抽汲表面 上’僅真空保留在工作腔室中。 3 201239196 在藉由封閉式循環冷卻器來冷卻之低溫泵系統中，冷 部裔通常為具有延伸穿過輻射屏蔽罩之冷指之兩階段致冷 器°致冷器之第二階段最冷之冷端位於冷指之尖端處。主 要抽沒表面或低溫板係在冷指之第二階段之最冷端處連接 至散熱片°此低溫板可為簡單金屬板、杯狀物或圍繞第二 階段散熱片配置且連接至第二階段散熱片的金屬隔板之陣 列’如（例如）在以引用之方式併入本文中的美國專利第 4’5 55’907號及第4,494,381號中。此第二階段低溫板亦可支 撑低度冷凝氣體吸附劑，諸如先前所陳述之活性碳或沸 石〇 致冷器冷指可延伸穿過杯狀輻射屏蔽罩之底座且與該 屏蔽罩同心。在其他系統中，冷指延伸穿過輻射屏蔽罩之 側面。此建構常有可用於置放低溫泵之較好地配合空間。 輻射屏蔽罩係於致冷器之第一階段之最冷端處連接至 散熱片或散熱台。此屏蔽罩以保護第二階段低溫板以使其 免党輻射熱之方式包圍第二階段低溫板。肖閉輻射屏蔽罩 之前陣列係藉由穿過該屏蔽罩或穿過熱支(如以引用之 方式併入本文中的美國專利第4,356,701中所揭示）之第一 階段散熱片來冷卻。 在已收集大量氣體之後，必須不時地再生低溫泵。再 生為釋放先前由低溫果捕獲之氣體的過程。再生通常係藉 由：：低溫泵恢復至環境溫度來完成，且氣體接著借助於 —階段泉而自低溫I移除。在氣體之此釋放及移除之後， 自再冷卻再:欠能夠自卫作腔室移除大量氣體起，低溫栗得 201239196 以恢復。 低溫泵之優點為氫氣捕獲機率，其為自低溫果外到達 該系之開口 σ卩的氫氣分子將在陣列之第二階段上被捕獲的 機率。捕獲機率直接與用於氫氣之果之速度、$每秒捕獲 之公升數相關。習知設計之較高速率菜具有對氫氣之20% 或以上之捕獲機率。 已提4各種$ &計以增加第ΙΠ型氣體之抽;及速度。舉 例而言，以引用之方式併人本文中的美國專利第4,7ΐ8,24ι 號提出第二階段陣列設計，其經建構以增加用於抽没不可 冷凝氣體之速度，同時限制系統之再生之頻率。其藉由敞 開第二階段低溫板以允許非冷凝氣體（諸如，线、氛氣 或氦氣）i已置放於低溫板之圓盤之内表面上的吸附劑材 料之較大接近性來完成此設計。此允許非冷凝氣體被更快 地吸附’因此增加非冷凝物之抽汲速度。同時，該第二階 段陣列經設計以便確保所有氣體分子首先撞擊低溫板之尚 未塗佈有吸附劑材料之表面。 其他栗設計（諸如，以引用之方式併入本文中之美國 專利第5,211，G22號中所描述之幻用具有多個孔口之板替 換第-階段之尖頂或通氣窗。與尖頂或通氣窗相比，該等 :口限制氣體至第二階段之流動。藉由限制至内部第二階 M由及區域之流動’允許一定百分比之惰性氣體保留在工 作空間中以提供惰性氣體之中等壓力（通常為1〇_3托或更 大）來用於最佳賤鑛。然而，諸如水之較高冷凝溫度氣體 二藉由别孔口板上之冷凝而迅速地自環境移除。 5 201239196 先前技術之實踐已進行以保護具有尖頂及濺鍍板之第 二階段’從而減小輻射熱衝擊第二階段、控制至第二階段 之第II型及III氣體流動速率且防止第I型（較高沸點）冷 凝氣體在較冷表面及吸附劑層上冷凝《輻射及流動速率之 減小降低第二階段低溫板表面及此等表面上之冷凝氣體以 及吸附劑之溫度。較低溫度導致增加的氣體捕獲能力且減 小再生循環之頻率。與含有提供輻射熱至第二階段低溫板 表面之直接視線之孔口之濺鍍板相比，尖頂提供非常良好 之輻射屏蔽。然而，與尖頂相比，當前先進技術濺鍍板將 第Π型及第in型氣體非常嚴格地限制至第二階段低溫板， 此導致此等氣體之較低抽汲速度。在一些應用中，抽汲速 度之此嚴格限制係較佳的，此係因為允許一定百分比之惰 性氣體保留在處理室之工作空間中以提供惰性氣體之中等 麼力來用於最佳濺鍍或其他處理。 【發明内容】 對具有提供經改良輻射阻擋與通過隔板之有限氣體流 動速率的容易製造之第一階段隔板及可攜載增加量之冷凝 氣體之第二階段陣列之低溫泵存在著市場需求。容易製造 之第—階段隔板具有孔口，該等孔口具有以一角度彎曲且 在該等孔口之邊緣處附接之擋板。第二階段陣列使用頂 板’該頂板在面積上大於該第二階段陣列之隔板。低溫果 可單獨或組合地使用容易製造之第一階段隔板及大面積頂 板中之每-者。 如所提到，低溫泵可包含第一階段前隔板，該第一階 6 201239196 段前隔板配置於該低溫泵之開口中。該前隔板具有實質上 覆蓋該低溫泵之該開口之面積。該前隔板具有複數個孔 口，每一孔口具有自該前隔板彎曲且在孔口之邊緣處附接 至該前隔板之擋板’且每一擋板配置於穿過該前隔板之路 徑中。該等孔口可為矩形、正方形、梯形、圓形、三角形 或任何其他形狀。該等擋板相對於該前隔板之表面較佳以 在10。與60。之間的角度彎曲，且最佳以在25。與35。之間的 角度彎曲。為達成更高速度但由於第二階段上之較高熱負 載’ 35°至45°之角度為較佳的。 可藉由首先提供金屬板來形成容易製造之前隔板。在 該圓形金屬板中形成複數個孔口，且自每一孔口的來自該 板的該金屬之至少一部分（擋板）保持在孔口之邊緣處附 接至該板。接著沿著邊緣相對於金屬板之表面呈一角度來 彎曲.金屬之該部分。該等孔口可為矩形、正方形、圓形、 梯形或三角形或任何其他形狀。每一孔口處之擋板可附接 至其各別孔口之最接近該前隔板之中心的邊緣。該等孔口 可配置於該前隔板上，以使得存在自該板之中心至板之邊 緣的至少一不具有孔口之路徑。該等孔口可（例如）藉由 雷射切割、水射流切割、機械切割、蝕刻及衝壓，之：少 一者而形成。 a本文中所描述的具有前隔板之低溫泵之優點包括製造 之簡單性及對來自該低溫泵所附接至的處理室之輻射之經 改良阻擋。本文中所描述的具有前隔板之低溫系之另一優 點為第Π型氣體及第m型氣體在低溫栗之第二階段陣列處 201239196 之經改良分佈。 視情況’低溫泵可具有第二階段陣列，該第二階段陣 列具有具第一投影面積（自通過至處理室之開口向低溫泵 中看的視點看）之複數個冷卻隔板，該複數個冷卻隔板可 配置為陣列，其中該等冷卻表面中之一或多者之至少一部 分塗佈有吸附劑材料。冷卻隔板之該陣列可水平地、垂直 地、以堆疊配置或以任何其他組合定向。該複數個冷卻隔 板中之每一者直接附接至第二階段致冷器，或該複數個冷 部隔板附接至連接至第二階段致冷器之托架。該第二階段 車歹j亦了具有頂板，该頂板麵接至該複數個冷卻隔板且配 置於該前隔板與該複數個冷卻隔板之間，該頂板與該複數 個冷卻隔板對準且具有大於該第一投影面積之第二投影面 積。該頂板之該投影面積可大於包圍該第二階段的該低溫 泵之輻射屏蔽罩的前開口面積之5〇%且較佳為約。然 而°玄頂板可具有大於忒等冷卻隔板之面積（其通常為輻 射屏蔽罩之約5 0% )的任何其他面積。 本文中所描述之具有大面積頂板之低溫泵的優點包括 在需要低溫泵之再生之前的冷凝之第„型氣體的增加之容 里大面積頂板之另優點為改良吸附劑材料與第η型氣 體之隔離，從而保留吸附劑材料以用於第ΠΙ型氣體。大面 積頂板對於上文所描述之前隔板特別有利。相較於使用濺 鍍板之習知前陣列，結合大面積頂板之前隔板允許來自處 理室之較少輻射到達隔板之第二階段陣列。減少之輻射降 低隔板之陣列/頂板之溫度，且特別降低最接近前隔板之隔 201239196 板/頂板及存在於最接近前隔板之隔板/頂板上之第π型冷 凝氣體的溫度。大面積頂板能夠捕獲較大體積之冷凝氣 體，同時維持該冷凝氣體可接受之表面溫度。 前隔板可用較佳成10。至60。且最佳成35。至45。之角度 的同心環替換。 【實施方式】 前述内容將自本發明之實例具體實例之以下較特定描 述顯而易I，如隨附圖式中所說明，在該等隨附圖式中相 同參考字元在不同視圖中始終指代相同部件。該等圖式未 必按比例繪製，而是將重點放在說明本發明之具體實例上。 以下為本發明之實例具體實例之描述。 在圖1Α及圖1Β中分別展示附接至處理室13之先前技 術圓形低酿泵6Α & 6Β之橫截面側視圖。低溫果6Α及6Β ，括低溫泉外殼12’其可沿著凸緣14直接安裝至處理室或 安裝至在其與連接至處理室13之處理管道"之間的中間 閘閥17。管道15包括可用以隔離低溫泵6與處理室13之 ]間17低皿栗6Α及6Β能夠對處理室丄3進行抽波。低 溫栗6A及6B句括r义艘k a丄* 累栓結合至耦接至處理室13之管道 1 5之低溫栗外殼12。/f氏、、田石+ 低'现策外殼12中之前部開口 1 6與處 理室13中之圓形開口逯诵 ^ 迷通°致冷器之兩階段冷指18穿過 谷器之圓柱形部分20突ψ 出至·低溫泵外殼12中。該致冷器 可為如Chellis箅人之盖™由 , 美國專利第3,218,815號中所揭示的201239196 VI. Description of the Invention: [Technical Field to Which the Invention Is Applicable] This application claims the benefit of U.S. Provisional Application No. 61/441,027, filed on Feb. . The complete teachings of the above application are hereby incorporated by reference. [Prior Art] Currently available cryopumps (whether using open low temperature cycles or closed low temperature cycle cooling) generally follow the same design concept. The low temperature second stage cryopanel, typically operated in the range of 4 K to 25 K, is the primary pumping surface. This surface is surrounded by a high temperature radiation shield that typically operates in the temperature range of 40 Κ to 13 〇, which provides radiation shielding for lower temperature arrays. The radiation shield typically includes an outer casing that is closed except at the array of front cryopanels positioned between the main pumping surface and the chamber to be evacuated. The first stage of the higher temperature front array acts as a pumping position for a high boiling point gas such as water vapor (referred to as a jth type gas). In operation, high boiling gases such as water vapor condense on the front array. The lower boiling gas passes through the front array and into the volume within the radiation shield. The π-type gas such as I gas is condensed in the second-order I array. Type III gases such as hydrogen, helium and helium have a perceptible vapor pressure. In order to capture the third gas, the inner surface of the second stage array may be coated with an adsorbent such as activated carbon, zeolite or molecular sieve. The process of adsorbing as a gas by physically retaining the material at a cryogenic temperature and thereby removing it from the scorpion. As the gas thus condenses or adsorbs onto the pumping surface, only the vacuum remains in the working chamber. 3 201239196 In a cryopump system cooled by a closed loop cooler, the cold part is usually the second stage of the two-stage refrigerator with a cold finger extending through the radiation shield. The cold end is located at the tip of the cold finger. The main pumped surface or cryopanel is attached to the heat sink at the coldest end of the second stage of the cold finger. The cryopanel can be a simple metal plate, a cup or a second stage heat sink configured and connected to the second Arrays of metal separators of the stage heat sinks are described, for example, in U.S. Patent Nos. 4'5 55'907 and 4,494,381, each incorporated herein by reference. This second stage cryopanel may also support a low condensing gas adsorbent, such as the activated carbon or zeolite chiller previously stated, which may extend through the base of the cup-shaped radiation shield and be concentric with the shield. In other systems, the cold finger extends through the side of the radiation shield. This construction often has a good fit space for placing cryopumps. The radiation shield is attached to the heat sink or heat sink at the coldest end of the first stage of the refrigerator. The shield encloses the second stage cryopanel in a manner that protects the second stage cryopanel from radiant heat. </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> </ RTI> <RTIgt; After a large amount of gas has been collected, the cryopump must be regenerated from time to time. It is reproduced as a process of releasing the gas previously captured by the low temperature fruit. Regeneration is usually accomplished by: cryogen pump recovery to ambient temperature, and the gas is then removed from cryogenic I by means of a stage spring. After the gas is released and removed, it is re-cooled again: it can recover from a large amount of gas by self-defense as a chamber, and the low temperature is 201239196 to recover. The advantage of a cryopump is the probability of hydrogen capture, which is the probability that hydrogen molecules from the low temperature outside the opening of the system will be captured in the second stage of the array. The probability of capture is directly related to the speed of the fruit used for hydrogen, and the number of liters captured per second. Conventionally designed higher rate dishes have a capture probability of 20% or more of hydrogen. Various types of $ & have been proposed to increase the pumping of the Dijon gas; and speed. For example, a second stage array design is proposed by way of example in U.S. Patent No. 4,7,8,24, the disclosure of which is hereby incorporated herein incorporated herein incorporated herein incorporated herein incorporated herein frequency. It is accomplished by opening the second stage cryopanel to allow for greater accessibility of the adsorbent material that has been placed on the inner surface of the disc of the cryopanel, such as a line, atmosphere or helium. This design. This allows the non-condensing gas to be adsorbed faster' thus increasing the pumping speed of the non-condensate. At the same time, the second stage array is designed to ensure that all gas molecules first strike the surface of the cryopanel that is not yet coated with the adsorbent material. Other chestnut designs, such as those described in U.S. Patent No. 5, 211, G22, which is incorporated herein by reference, incorporates a plurality of orifices to replace the apex or venting window of the first stage. In contrast, the port restricts the flow of gas to the second stage. By limiting the flow to the internal second order M from the region, 'allows a certain percentage of inert gas to remain in the workspace to provide equal pressure in the inert gas ( Typically 1 〇 3 Torr or larger for optimum bismuth ore. However, higher condensing temperature gases such as water are quickly removed from the environment by condensation on the orifice plate. 5 201239196 Previous The practice of technology has been carried out to protect the second stage of the apex and sputter plate' to reduce the second stage of radiant heat shock, to control the gas flow rate of Type II and III to the second stage and to prevent Type I (higher boiling point) Condensed gas condenses on the colder surface and the adsorbent layer. The decrease in radiation and flow rate reduces the surface of the cryopanel in the second stage and the temperature of the condensing gas and adsorbent on the surface. Lower temperature This results in increased gas capture capability and reduces the frequency of the regeneration cycle. The apex provides very good radiation shielding compared to sputtered plates containing orifices that provide radiant heat to the direct line of sight of the second stage cryopanel surface. However, with the apex In contrast, current state-of-the-art sputters restrict the first and first in-type gases very strictly to the second stage cryopanel, which results in lower pumping speeds for these gases. In some applications, the pumping speed is This strict limitation is preferred because a certain percentage of the inert gas is allowed to remain in the working space of the processing chamber to provide an inert gas for optimum sputtering or other processing. There is a market demand for a first stage separator that provides improved radiation barrier and a limited gas flow rate through the separator, and a second stage array of cryogenic gas that can carry an increased amount of condensed gas. The stage baffle has apertures having baffles that are bent at an angle and attached at the edges of the apertures. The second stage array enables The top plate 'the top plate is larger in area than the second stage array. The low temperature fruit can be used alone or in combination for each of the first stage separator and the large area top plate which are easy to manufacture. As mentioned, the cryopump The first stage front baffle may be included, and the first stage 6 201239196 segment front baffle is disposed in the opening of the cryopump. The front baffle has an area substantially covering the opening of the cryopump. The front baffle has a plurality of apertures, each aperture having a baffle bent from the front baffle and attached to the front baffle at an edge of the aperture and each baffle disposed in a path through the front baffle The apertures may be rectangular, square, trapezoidal, circular, triangular or any other shape. The baffles are preferably curved at an angle of between 10 and 60 with respect to the surface of the front spacer, and It is preferred to bend at an angle between 25. and 35. To achieve a higher speed, it is preferred because of the higher thermal load on the second stage '35° to 45°. The prior separator can be formed by first providing a metal plate. A plurality of apertures are formed in the circular metal plate, and at least a portion (baffle) of the metal from the plate from each aperture is attached to the plate at the edge of the aperture. The portion of the metal is then bent along the edge at an angle relative to the surface of the metal sheet. The apertures can be rectangular, square, circular, trapezoidal or triangular or any other shape. A baffle at each orifice can be attached to the edge of its respective orifice that is closest to the center of the front baffle. The apertures may be disposed on the front bulkhead such that there is at least one path having no apertures from the center of the panel to the edge of the panel. The apertures can be formed, for example, by laser cutting, water jet cutting, mechanical cutting, etching, and stamping, one of which is less. a Advantages of the cryopump having a front baffle as described herein include the simplicity of manufacture and improved barrier to radiation from the processing chamber to which the cryopump is attached. Another advantage of the low temperature system having a front separator as described herein is the improved distribution of the third gas and the m-type gas at the second stage array of low temperature pumps 201239196. Optionally, the cryopump may have a second stage array having a plurality of cooling baffles having a first projected area (as viewed from a view through the opening to the processing chamber to the cryopump), the plurality of cooling baffles The cooling baffles can be configured as an array wherein at least a portion of one or more of the cooling surfaces are coated with a sorbent material. The array of cooling spacers can be oriented horizontally, vertically, in a stacked configuration, or in any other combination. Each of the plurality of cooling partitions is attached directly to the second stage refrigerator, or the plurality of cold partitions are attached to a bracket connected to the second stage refrigerator. The second stage rudder j also has a top plate that is connected to the plurality of cooling partitions and disposed between the front partition and the plurality of cooling partitions, the top plate and the plurality of cooling partitions And having a second projected area greater than the first projected area. The projected area of the top plate may be greater than 5% and preferably about 5% of the front opening area of the radiation shield surrounding the second stage. However, the top plate may have any other area than the area of the cooling baffle (which is typically about 50% of the radiation shield). The advantages of the cryopump having a large-area top plate as described herein include the addition of a large-area top plate in the volume of the condensed gas before the regeneration of the cryopump is required to improve the adsorbent material and the n-type gas. Isolation, thereby retaining the sorbent material for the ΠΙ-type gas. The large-area top plate is particularly advantageous for the prior separators described above. Compared to the conventional front array using sputtered plates, combined with the large-area top plate before the separator Allowing less radiation from the process chamber to reach the second stage array of the separator. The reduced radiation reduces the temperature of the array/top plate of the separator and particularly reduces the spacing of the frontmost separator to the 201239196 plate/top plate and exists closest to The temperature of the π-type condensing gas on the separator/top plate of the separator. The large-area top plate can capture a large volume of condensed gas while maintaining an acceptable surface temperature of the condensed gas. The front separator can be preferably used to 10. 60. And is preferably a concentric ring replacement at an angle of 35 to 45. [Embodiment] The foregoing will be described in more detail below from the specific examples of the present invention. The same reference numerals are used throughout the drawings to refer to the same parts in the various figures. The drawings are not necessarily drawn to scale, but rather In the following, specific examples of the invention are described. The following is a description of specific examples of the invention. Cross-sections of prior art circular low-brew pumps 6Α & 6Β attached to the processing chamber 13 are shown in Figures 1A and 1B, respectively. Side view. Low temperature fruit 6 Α and 6 Β , including a low spa shell 12 ′ which can be mounted directly to the processing chamber along the flange 14 or to an intermediate gate valve 17 between it and the processing conduit connected to the processing chamber 13 . The pipe 15 can be used to isolate the cryopump 6 from the processing chamber 13 and the lower chambers 6 and 6 can pump the processing chamber 。 3. The low temperature pump 6A and 6B include the r-boat ka丄* The low temperature chestnut shell 12 of the pipe 15 coupled to the processing chamber 13 is a circular opening in the processing chamber 13 and a circular opening in the processing chamber 13 °The two-stage cold finger of the refrigerator is 18 through the cylindrical portion 20 of the grain. In the outer casing 12. The chiller can be as disclosed in the Chellis 箅 之 盖 , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,
Gifford-McMahon 致冷器。、人 & 7盗。令指18中之兩階段置換器係藉 由馬達22驅動。關於每一 循％，在壓力下引入至冷指中之 9 201239196 氦m脹且因此冷卻且接著經由管線⑶ne)排出。第一階 鲛散熱片或散熱台28係安裝於致冷器之第一階段π之冷 端處類似地，散熱片30係安裝至第二階段32之冷端處。 主要抽汲表面為安裝至第二階段散熱台30之隔板陣列 34 #此陣列較佳保持在20 Κ以下之溫度下以便使低冷凝溫 度孔體冷凝。杯狀輻射屏蔽罩36係結合至第-階段散熱台 28冷才曰之第二階段32延伸穿過該輕射屏&罩中之開口。 此屏蔽罩包圍第二階段陣列34至該陣列之後部及側部以使 最小化輕射對該陣列之加熱。較佳地，此ϋ射屏蔽罩之溫 度約小於1 3 0 Κ。 圖_ 1Α展不前低溫板陣列38，其既充當用於隔板陣列 λ*辨&射屏蔽罩，又充當用於諸如水蒸氣之較高沸騰溫度 '的：溫抽沒表面。此陣列包含藉由徑向支撐桿4"吉合 窗39。支撐桿41係安裝至輻射屏蔽罩36 1射屏 mV"支撐前低溫板陣列38 ’又充當自散熱片28至前 低恤板陣列3 8之熱路徑。 敎接：？示另一前低溫板設計，其包括與輕射屏蔽罩36 ;^之福板33’其既充當用於第二階段抽汲 射屏蔽罩，並且充當用於諸如 ： 之低溫抽汲表面。前㈣33較^騰溫度氣體 敍L一 板33係藉由托架37附接至輻射屏 敵罩36。前隔板33具有限制龢你地机 鱼 較低/弗點溫度氣體至第二階段 陣列之流動的複數個孔口 3 5。 6亥刖隔板以選擇性方式抵你田 捭為κ姑 式起作用，此係因為該前隔板保 持在接近第-階段散熱片之溫度（在5〇W之間） 201239196 的溫度下。當較高冷凝溫度氣體在隔板自身上凍結時，孔 口 3 5限制此等較低冷凝溫度氣體傳遞至第二階段。如上所 述，藉由限制至内部第二階段抽汲區域之流動，允許一定 百刀比之惰性氣體保留在工作空間中以提供惰性氣體之中 4壓力（通常為1〇托或更大）來用於最佳濺锻。總而言 之，在到達低溫泵口 1 6之氣體中，較高沸騰溫度氣體係藉 由則隔板上之冷凝而自環境移除，同時限制較低溫度氣體 至第二階段抽汲表面之流動。流動限制導致工作腔室中之 壓力較高。 圖2展示具有前隔板40之具體實例之圓形低溫泵7， 且圖3A及圖3B展示與低溫泵隔離之前隔板4〇。前隔板4〇 具有複數個孔口 42，每一孔口具有與其相關聯之擋板44。 圖3 A展示前隔板40之俯視圖。前隔板40攜載複數個孔口 35刖隔板40亦可攜載複數個孔46，該複數個孔可收納鉚 釘、螺釘或其他扣件（圖中未示）以將前隔板 40附接至托 木37。在所展示之具體實例中，該複數個孔口 35係以提供 不具有孔口 35之區48的圖案配置在前隔板4〇上。此等區 48允許刚隔板4〇之中心5〇與前隔板之孔μ及周邊π 之間的較兩導熱性。—般而言，前隔板40係經由孔46在 托木37處熱耦接至輻射屏蔽罩，且亦可在前隔板與輻 射屏蔽罩36接觸的周邊47處耦接。圖2展示座落在輻射 屏蔽罩36内之刖隔板4〇。或者，前隔板40可配置在輻射 蔽罩36之上。圖3Β展示圖3Α中所展示之截面A-Α處 的月J隔板40之側視圖橫截面。前隔板中之每一孔口 μ 11 201239196 具有擋板44。每一擋板44係在其各別孔口 35之邊緣48處 附接至前隔板40 » 圖3C展示用於圓形低溫泵之具有矩形孔口 51的前隔 板49之替代具體實例的透視圖。圖3c自面向處理室13之 側展示前隔板49。每一矩形孔口 51具有在摺線55處附接 之相關聯檔板5 3。用於每一孔口 5 1之指線5 5位於最接近 前隔板49之中心之孔口邊緣處，以使得自處理室13至隔 板陣列34之無阻擋路徑穿過孔口 5 1以徑向方式由前隔板 之中心向外。此徑向向外路徑將來自處理室之相對熱氣流 引導離開以免首先衝擊隔板陣列34，從而減少隔板陣列上 之熱負載。此徑向向往路徑亦減少隔板之第二階段陣列34 上之輻射負載，此係因為輻射亦被引導離開隔板陣列34。 身又而§ ’增加前隔板40上之孔口 35之數目及將孔 口 35均勻地分佈在前隔板4〇上導致穿過孔口 35之第π型 氣體較均勻地碰撞在低溫泵中之隔板陣列34上。然而，增 加具給定大小之孔口 35之數目及均勻地間隔孔口 35減小 不具孔口 35之區48之大小，從而減小前隔板4〇之導熱性， 此可增加操作中低溫泵中之前隔板4〇的溫度。又增加孔 口 35之數目可能需要較小孔口 35，且較小孔口乃較容易 被冷凝氣體堵住。 圖4為前隔板40中之圓形孔口 35的透視近視圖。孔 口 35為前隔板40所包圍。擋板44係在摺線52處附接至 前隔板40且相對於前隔板40以角度α定位。角度α較佳 為在與60。之間的角度，且更佳為在20〇與4〇〇之間的角 12 201239196 度，且最佳為在25。與35。之間的角。選擇角度〇1為阻擋輻 射（較小角度。〇與改良至第二階段之氣體流動（較大角度 a)之間的折衷，且理想角度α可取決於特定應用及抽汲需 要。 圖5展示在使擔板44彎曲之前的前隔板4〇中之圓形 孔口 35的俯視近視圖。通常，孔口 35係藉由在前隔板4〇 中切開間隙54而形成。可使用任何移除手段（包括（但不 限於）雷射切割、水射流切割、钮刻及機械切割）形成該 間隙。除了間隙54不能連續地完全圍繞孔口 35之邊緣之 夕卜’間隙54界定孔口 35之邊緣。附接至擋板44之摺線52 摺線52具有長度L)使孔口 35之邊緣完整。間隙54具 有寬度除了 一些輻射將穿過間隙54到達隔板陣列34 卜來自腔至13之穿過孔口 35之輻射將由擋板44阻擔。 需要最小化間隙54之寬度G。可能藉由形成孔口 35 藉由衝壓）而使間隙54具有零寬度G，在該情況 衡愚“反44係藉由自前隔板4〇剪切擋板而形成。然而， 般需要造價高昂之工具且在未訂購新衝壓工具之情 雷射切1::應改變（例如’不同孔口大小、形狀或圖案)。 。'方法可形成小至0.020吋的間隙。 -般::具::：中，圓形孔口具有二分之-叶之直徑》 導性命：别隔板中之總面積愈大，氣體通過板之傳 佈。^ 多較小孔允許氣體在第二階段上之較均勻分 可Y孔不應太小以致於被冷凝氣體堵住。圓形孔口 (例如）具有在。·25时至i叶之範圍中之直徑。 13 201239196 圖6展示前隔板60中之矩形孔口 62的俯視近視圖。 矩形孔口 62具有間隙66，除了間隙66不能連續地完全圍 繞孔口 62之邊緣之外，該間隙66界定孔口 62之邊緣。附 接至擋板68之摺線64 (摺線64具有長度L )使孔口 62之 邊緣完整。摺線64較佳配置在矩形孔口 62之最長尺寸上。 舉例而言，在一具體實例中，矩形孔口 62具有二分之一时 長乘以一吋長之尺寸，且摺線64較佳配置在一吋長之側 上。矩形孔口之尺寸可在^至5:1之長度對寬度比的範圍 内。矩形孔口之優點包括易於製造性及針對給定孔口 62大 小的檔板68與前隔板60之間的經改良之導熱性（與圓形 孔口相比）。因為摺線64之長度在矩形孔口上比在大小相 當之圓形孔口上大，所以導熱性得到改良。 圖6展示前隔板70中之三角形孔口 62的俯視近視圖。 三角形孔口 72可為類似等邊三角形或類似等腰三角形之形 狀。二角形孔口 72具有間隙76，除了間隙％不能連續地 完全圍繞三角形孔口 72之邊緣之外，該間隙％界定三角 形孔口 72之邊緣。附接至擋板78之摺線74(摺線74具有 長度L)使孔口 72之邊緣完整。再次，指線74較佳配置在 三角形孔口 74之最長尺寸上。若三角形孔口 72為類似等 邊三角形之形狀，則摺線74可位於孔口72之㈣邊緣上。 然而’若三角形孔口 72為類似等腰三角形之形狀，則可較 佳將摺線74配置在孔口 72之較短、非相等長度邊緣上以 相對於剩餘邊緣保持指疊對稱。_ 5至圖7僅展示前隔板 中之孔口之實例形狀。亦可使用其他形狀。圖2中之孔口 14 201239196 42可包括具此等形狀中之任一者之孔口，且孔口 42可包括 不同形狀之混合。 圖8 A展示具有具複數個孔口 82之前隔板8〇之低溫果 8的另一具體實例。在此具體實例中，擋板84經配置以使 得該等擋板指向處理室1 3且遠離第二階段陣列34。類似圖 2,孔口 82可包括具任何形狀之孔口 ’且可包括不同形狀 之混合。當工作腔室13之側上比第二階段陣列34之側上 存在更多的空間時，可以將擋板面向處理室13之方式定位 前隔板80。再次，該等檔板經定向以引導流離開第二階段。 圖8B展示具有複數個孔口 91之前隔板85之另一具體 實例。前隔板85包括堆疊且接合在一起的多個層87、89。 層87包括如上文關於圖3至圖7所描述之孔口 91及檔板 93 ^層89包括孔口 91 ’但不包括擋板93。圖祁僅展示兩 個層87、89。然而’前隔板可由兩個以上層形成。該多個 層可藉由任何手段（包括（但不限於）熔接、焊接、柳釘、 螺釘、螺栓及黏合劑）接合在一起。 圖9展示具有大面積頂板9〇之低溫泵9之具體實例， 該大面積頂板可定位於隔板之第二階段陣列34之最上部隔 板之上或如圖所展示替換隔板之第二階段陣列^之最上部 隔板。大面積頂板90導致其本身與輻射屏蔽罩％之間的 間隙⑴匕隔板陣列34之剩餘隔㈣輕射屏蔽罩％之間的 間隙94小。針對給定量之經抽没之第π型氣體，大面積頂 :90減小冷凝氣體之厚度，此導致抽汲期間的遍及冷凝材 之厚度之較小溫差且亦減小返回基線溫度之工作循環之 201239196 間所需的時間量，如τ文所描述^大面積頂板9Q亦將允許 抽汲更多第π型氣體，此係因為對於相同厚度之冷凝氣 v凝氣體之總體積將由於較大面積而增加。大面積頂 板90減小到達隔板陣列34之剩餘隔板及剩餘隔板之下側 上的吸附劑材料（圖中未示）的第Π型氣體之量。 圖丨〇展示第二階段陣列之圓形大面積頂板9〇及建置 於其上之冷凝氣體層1〇2的側視圖橫截面。該等冷凝氣體 由冷凝之第11型氣體組成。如上所述，來自處理室13之特 定氣體穿過前隔板且在第二階段陣列之頂板9〇上冷凝。此 等乳體冷凝成具有厚度【之層1〇2，且該等氣體具有導熱係 數κ。如上所述，大面積頂板9〇被維持在極低溫度L下。 冷凝氣體102之表面處之溫度將為比I暖之不同溫度丁2。 备工作腔室間置且無額外氣體將添加至低溫泵時，L最後 將降至等於（或非常接近等於）Τιβ然而，當新氣體自工作 腔室引入至低溫泵中且在已冷凝之氣體1〇2之上冷凝時， 丁2高於丁2與Tl之間的差為冷凝氣體1〇2之厚度（、冷 凝氣體102之熱導率&及在板9〇上冷凝之進入氣體之溫度 及到達速率的函數。冷凝氣體層102愈厚，在處理室13令 之工作循環之後I返回Tl所需時間愈長。若l在臨限溫 度以上，則低溫栗不能有效地自工作腔室抽沒氣體，且丁2 在臨限溫度以上之時間愈|，工作腔冑13不可使用之時期 愈長。因此’在自工作腔室接收氣體之後τ2降至臨限位準 以下所需的時間量為用以判定何時再生低溫泵之因素。最 小化冷凝氣體102之厚度因此對最Α化再生循環之間的時 16 201239196 間量為有益的。 圖11A及圖11B說明大面積頂板9〇如何最小化冷凝氣 體102之厚度。首先，對於諸如圖nA及圖UB中所展示 之板的圓柱形板，請注意，冷凝氣體1〇2形成大致圓柱形 體積（忽視稍微圓形之側及包覆至大直徑頂板9〇之相反側 上之冷凝氣體）。圖11A展示具有小直徑Di之圓形頂板ιι〇 的側視圖橫截面。板11〇為來自隔板陣列34之頂部隔板之 代表。為簡單起見，忽視隔板陣列34中所展示之有角度之 邊緣。頂板11〇在其之上具有冷凝氣體層112〇冷凝氣體us 具有體積V且為圓柱形之形狀。圖11B展示具有大直徑 之圓形大面積頂板114的側視圖橫截面，其中h大於。 大面積頂板114在其之上具有冷凝氣體層116<>冷凝氣體（μ 具有與板110上之冷凝氣體112相同的體積v。然而，冷凝 氣體U6之厚度t2小於圖11A之板11〇上之冷凝氣體二2 之厚度h。圓柱體之體積為冗d2/4乘以厚度t。因此，將板 之直徑自D1增加至A意謂著相同體積v之冷凝氣體 及H6將其厚度自ti減小至t2。對於相同體積之霜，大面 積頂板114因此可比板110更快地自A返回Τι。又，大面 積頂板114可在可接受之時間量中將 '減小至I且積聚在 大面積頂板上之冷凝氣體比才反110可積聚之冷凝氣體多。 又’因為對於給定體積之冷凝氣體116，Τ丨與丁2之間的差 2小，所以大面積頂板114之溫度τ〖可高於小頂板110之 溫度T〗，同時仍維持冷凝氣體丨16之可接受溫度h。 返回圖9大面積頂板90亦藉由捕獲較多之第η型氣 17 201239196 體防止彼等第π型氣體到達隔板陣列34中之剩餘隔板及 剩餘隔板之-些或全部上之吸附劑材料（圖中未示）來改 良低溫系。第Π型氣體將在吸附劑材料上冷凝，但此冷凝 減小吸附劑材料吸附第m型氣體之能力。第π型氣體較佳 在大面積頂板9〇上冷凝以保存吸附劑材料用於第m型氣 體。大面積頂板90提供比隔板陣列34之剩餘隔板與輻射 屏蔽罩36之間的間隙94小的大面積頂板9〇之邊緣與輕射 屏蔽罩36之間的間隙92。較小間隙％減小在大面積頂板 9〇與輻射屏蔽罩36之間穿過的第π型氣體之量。然而， 較小間隙亦使到達隔板陣列34令之剩餘隔板上之吸附劑材 料的第III型氣體之移動減慢，藉此減小彼等氣體之抽汲速 度。又，大面積頂板90之較大表面積使大面積頂板9"交 容易受來自工作腔室之輻射影響。增加大面積頂板9〇之輕 射曝露增加大面積頂板9〇因此第二階段之熱負載亦然。 在根據本發明之圓形低溫泵之一具體實例中圓形大 面積頂板90之直徑〇2為6·5忖且隔板陣列34中之剩餘隔 板之直徑D,為5.28吋。在此建構之一測試中，發現第工工工 型氣體之抽沒速度減小了大約12%。然而，其他直徑亦為 可能的。圓形大面積頂板90可具有大於隔板陣列34之直 從的任何直徑，同時在該板與輻射屏蔽罩36之間留下間隙 乂提供第III型氣體之足夠抽汲速度。隔板陣列34通常具 有為輻射屏蔽罩36之直徑之大約7〇%的直徑。大面積頂板 9〇可具有在輻射屏蔽罩36之直徑之大約7〇%與之間的 ^對於非圓形低溫泵，大頂板具有在輪射屏蔽罩之橫 18 201239196 截面積之50%與95%之間的橫截面積。較佳地 面積將為輕射屏蔽罩之前開口面積的㈣至9〇%。頂板： 將吸附劑支撐於其底表面上。 圖U為展不用於特定圓形低溫泵之大面積頂板之各種 A J的測忒結果的曲線圖。肖曲線圖展示隨著冷凝氣體之 體積增加時的冷凝氣體（「霜」）之表面溫度。對於測試中 斤使用之特疋低〉显果，冷凝氣體之表面溫度之臨限溫度1 為27 K，較尚溫度將為不可接受的且將需要再生低溫泵。 該曲線圖展示較大面積頂板可固持較大體積之冷凝氣體， 同時將溫度維持在臨限溫度12〇之下。舉例而言，在冷凝 氣體之表面溫度超過臨限溫度12〇之前，具有5吋之直徑 的圓形大面積頂板i可積聚大約2 3立方吋之冷凝氣體。在 另貫例中’在冷凝氣體之表面溫度超過臨限溫度120之 前，具有5.5吋之直徑的圓形大面積頂板2可積聚大約2.7 立方吋之冷凝氣體。在又一實例中，在冷凝氣體之表面溫 度超過臨限溫度12〇之前，具有6.0吋之直徑的圓形大面積 頂板3可積聚大約3.丨立方吋之冷凝氣體。在第四實例中， 在冷凝氣體之表面溫度超過臨限溫度12〇之前，具有6.5吋 之直徑的圓形大面積頂板4可積聚大約2.6立方对之冷凝氣 體。 圖13展示併有前隔板40 (諸如，上文中在圖·3至圖8 中所描述之前隔板）及大面積頂板90 (諸如，在圖9至圖 11中所描述之板）兩者之低溫果1.0的侧視圖橫截面。前隔 板40與大面積頂板90之組合為有益的。前隔板40允許來 19 201239196 自處理至13之比使用減鐘板之習知前陣列少的輻射到達隔 板之第二階段陣列34及頂板90。減小之輻射減小隔板陣列 之度’且洋&之降低最接近前隔板4〇之隔板/頂板9〇 此度如上文所解釋，大面積頂板90能夠捕獲較大體積 之冷凝氣體及維持可接受之溫度。 圖14為展示併有前隔板4〇及大面積頂板兩者之低 泵1 〇之優點的圖表。圖14展示低溫泵能夠在各種流動 速率下維持之依據已抽汲之總體積的真空之測試結果。對 貝丨Π式中所使用之低溫栗，不能超過1 X 1 〇 _6托之臨限壓力 122。若低溫泵不能將壓力維持在臨限壓力122以下，則低 溫泵必須再生。該圖表展示正以1〇〇標準立方公分/分鐘 (seem」）之速率124抽汲氣體之標準低溫泵（諸如，圖i 中所展示之低溫泵）在其不能將壓力維持在臨限壓力i22 以下之前可抽汲大約1750公升。與之相比，以23〇sccm之 速率126抽汲氣體之標準低溫泵在其不能將壓力維持在臨 限壓力122以下之前僅可抽汲大約42〇公升之氣體。併有 刖隔板40及大面積頂板9〇兩者之低溫泵1〇 (其正以23〇 seem 128進行抽汲）可在其不能將壓力維持在臨限壓力122 以下之前抽汲超過^00公升。僅具有前隔板4〇及大面積 頂板90中之一者之低溫泵可呈現以23〇sccm所說明之兩個 速率126及128之間的結果。 圖15A及圖15B說明利用大面積頂板9〇之本發明之又 一具體實例。在此具體實例中，前陣列包含支撐在耦接至 輻射屏蔽罩之壁的桿132及134上之同心環13〇。雖然該等 20 201239196 :心環可包括如圖"所說明之尖頂，但為了增加速度， 每-％為僅在一個方向上成角度之截頭圓錐體環。較佳角 度在10。至60。之範圍中，但更佳在35。至^。之範圍中。角 度之選擇為速度與第二階段上之輕射熱負载之間的取捨。 較佳地’每一環之外徑大約與下一較大環之内徑相同或恰 好大於下-較大環之内徑。雖然該等環經展示為由輕射屏 蔽罩之側壁支# ’但該等環可由延伸至輻射屏蔽罩之底座 的縱向延伸之支柱支撐。 在其他具體實例中，如上所述，具有前隔板陣列及/或 頂板之低皿泵在形狀上可為非圓形的。此等非圓形低溫 泵之實例係在美國專利第6，155，G59號中描述，該案之内容 以全文引用之方式併入。對於矩形低溫泉，大頂板較佳可 覆蓋輻射屏蔽罩之橫截面積之50%至98°/。。在其他具體實 例中，如上所述，具有前隔板陣列及/或大頂板之低溫泵可 為現場低溫系或附屬系。此等現場低溫泵及附屬低溫泵之 實例係在專利合作條約申請案第pcT/US2〇〇9/〇65i68號中 描述，該案之内容以全文引用之方式併入。 本文中所引用之所有專利、公開申請案及參考文獻之 教示係以全文引用之方式併入。 雖然已參考本發明之實例具體實例特定地展示並描述 了本發明’但熟習此項技術者將理解’在不脫離由附加之 申明專利範圍涵蓋的本發明之範疇之情況下可作出形式及 細節上之各種改變。 【圖式簡單說明】 21 201239196 圖1A為先前技術低溫泵之側視圖橫截面； 圖1B為另一先前技術低溫系_之側視圖橫截面； 圖2為具有前隔板之具體實例之低溫泵的側視圖橫截 面； 圖3A為具有圓形孔口之前隔板之具體實例的俯視圖； 圖3B為圖3 A中所展示之前隔板之具體實例的側視圖 橫截面； 圖3C為具有矩形孔口之前隔板之具體實例的俯視圖； 圖4為圖3A及圖3B中所展示之前隔板之具體實例中 的孔口及擋板的透視圖； 圖5為圖3八、圖3B及圖4中所展示之前隔板中之孔 口的俯視圖； 圖6為前隔板中之矩形孔口的俯視圖； 圖7為前隔板中之三角形孔口的俯視圖； 圖8A為具有前隔板之另一具體實例之低溫泵的側視圖 橫截面； 圖8B為前隔板之側視圖橫截面； 圖9為具有大面積頂板之另一具體實例之低溫泵的側 視圖橫截面； 圖1〇為圖9中所展示之大面積頂板的側視圖橫截面； 圖11A為第二階段頂板之側視圖橫截面； 圖11B為第二階段大面積頂板之側視圖橫截面； 圖12為展示具有不同直徑之各種大面積頂板之冷凝氣 體容量的圖表； 22 201239196 圖1 3為具有結合大面積頂板之具體實例的前隔板之具 體實例之低溫泵的側視圖橫截面； 圖14為展示各種低溫泵建構之抽汲能力的圖表； 圖1 5 A為具有同心環之前陣列及大面積頂板之低溫泵 的側視圖橫截面；及 圖15B為圖15A之前陣列之平面圖。 【主要元件符號說明】 23Gifford-McMahon refrigerator. , people & 7 stolen. The two-stage displacer in index finger 18 is driven by motor 22. With respect to each cycle %, it is introduced under pressure into the cold finger 9 201239196 胀m swells and thus cools and is then discharged via line (3) ne). The first stage heat sink or heat sink 28 is mounted at the cold end of the first stage π of the refrigerator. Similarly, the heat sink 30 is mounted to the cold end of the second stage 32. The main pumping surface is a spacer array 34 mounted to the second stage heat sink 30. This array is preferably maintained at a temperature below 20 Torr to condense the low condensation temperature aperture. The cup-shaped radiation shield 36 is coupled to the second stage 32 of the first stage heat sink 28 to extend through the opening in the light shot screen & cover. This shield encloses the second stage array 34 to the rear and sides of the array to minimize the heating of the array by light. Preferably, the temperature of the radiation shield is less than about 130 Κ. Figure _1 shows an array of cryopanel arrays 38 that serve both as a spacer array and as a higher boiling temperature for water vapor. This array consists of a radial support bar 4" The support rods 41 are mounted to the radiation shield 36 1 screen mV" the support front cryopanel array 38' again acts as a thermal path from the heat sink 28 to the front low sheet array 38. Connection:? Another front cryopanel design is shown that includes a light shield shield 36' that acts both as a second stage sniffer shield and serves as a low temperature twitch surface for use. The front (four) 33 is more than the temperature gas. The panel 33 is attached to the radiant screen enemy cover 36 by the bracket 37. The front bulkhead 33 has a plurality of apertures 35 that limit the flow of the lower/frozen temperature gas to the second stage array. The 6 刖 刖 以 以 以 以 以 以 以 以 以 以 以 以 以 以 以 以 以 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 When the higher condensing temperature gas freezes on the separator itself, the orifices 35 limit the transfer of these lower condensing temperature gases to the second stage. As described above, by limiting the flow to the internal second stage pumping zone, a certain hundred cycles of inert gas is allowed to remain in the workspace to provide 4 pressures (usually 1 Torr or greater) among the inert gases. For optimum splash forging. In summary, in the gas that reaches the cryopump port 16, the higher boiling temperature gas system is removed from the environment by condensation on the separator while limiting the flow of the lower temperature gas to the second stage pumping surface. Flow restrictions result in higher pressures in the working chamber. 2 shows a circular cryopump 7 having a specific example of a front baffle 40, and FIGS. 3A and 3B show the baffle 4〇 before being isolated from the cryopump. The front bulkhead 4 has a plurality of apertures 42 each having a baffle 44 associated therewith. FIG. 3A shows a top view of the front bulkhead 40. The front baffle 40 carries a plurality of apertures 35. The baffle 40 can also carry a plurality of holes 46 that can receive rivets, screws or other fasteners (not shown) to attach the front baffle 40 Connected to the tow 37. In the particular embodiment shown, the plurality of apertures 35 are disposed on the front bulkhead 4 in a pattern that provides a region 48 that does not have apertures 35. These zones 48 allow for the two other thermal conductivities between the center 5 of the baffle 4 and the hole μ and the periphery π of the front baffle. In general, the front bulkhead 40 is thermally coupled to the radiation shield at the pallet 37 via the aperture 46 and may also be coupled at the perimeter 47 where the front bulkhead contacts the radiation shield 36. Figure 2 shows the 刖 spacer 4〇 seated within the radiation shield 36. Alternatively, the front bulkhead 40 can be disposed over the radiation shield 36. Figure 3A shows a side cross-sectional view of the Moon J spacer 40 at section A-Α shown in Figure 3A. Each orifice in the front baffle μ 11 201239196 has a baffle 44. Each baffle 44 is attached to the front bulkhead 40 at its edge 48 of its respective aperture 35. Figure 3C shows an alternative embodiment of a front bulkhead 49 having a rectangular aperture 51 for a circular cryopump. perspective. Figure 3c shows the front bulkhead 49 from the side facing the processing chamber 13. Each rectangular aperture 51 has an associated link plate 53 attached at a fold line 55. The finger line 5 5 for each aperture 51 is located at the edge of the aperture closest to the center of the front partition 49 such that an unobstructed path from the processing chamber 13 to the array of partitions 34 passes through the aperture 51 The radial mode is outward from the center of the front bulkhead. This radially outward path directs the relative hot gas flow from the process chamber away from first impacting the baffle array 34, thereby reducing the thermal load on the baffle array. This radially upward path also reduces the radiation load on the second stage array 34 of the spacers because the radiation is also directed away from the spacer array 34. Further, § 'increasing the number of orifices 35 on the front baffle 40 and evenly distributing the orifices 35 on the front baffle 4〇 causes the π-type gas passing through the orifices 35 to collide more uniformly in the cryopump On the baffle array 34. However, increasing the number of apertures 35 of a given size and evenly spacing the apertures 35 reduces the size of the region 48 without the apertures 35, thereby reducing the thermal conductivity of the front bulkhead 4, which may increase the low temperature during operation. The temperature of the front baffle 4 in the pump. Increasing the number of orifices 35 may require smaller orifices 35, and the smaller orifices are more susceptible to blockage by condensing gases. 4 is a perspective close-up view of the circular aperture 35 in the front bulkhead 40. The aperture 35 is surrounded by the front bulkhead 40. The baffle 44 is attached to the front bulkhead 40 at the fold line 52 and is positioned at an angle a relative to the front bulkhead 40. The angle α is preferably at 60. The angle between, and more preferably between 20〇 and 4〇〇, is 12 201239196 degrees, and the best is at 25. With 35. The angle between. The choice of angle 〇1 is a compromise between blocking radiation (smaller angles and turbulence and gas flow to the second stage (larger angle a), and the ideal angle α may depend on the particular application and pumping needs. Figure 5 shows A top plan view of the circular aperture 35 in the front bulkhead 4〇 prior to bending the support plate 44. Typically, the aperture 35 is formed by slitting the gap 54 in the front bulkhead 4〇. Any movement can be used. The gap is formed by means including, but not limited to, laser cutting, water jet cutting, button engraving, and mechanical cutting. Except that the gap 54 cannot continuously completely surround the edge of the aperture 35, the gap 54 defines the aperture 35. The edge of the fold line 52 attached to the baffle 44 has a length L) that completes the edge of the aperture 35. The gap 54 has a width except that some of the radiation will pass through the gap 54 to the baffle array 34. The radiation from the cavity to the through hole 35 will be blocked by the baffle 44. It is desirable to minimize the width G of the gap 54. It is possible to have the gap 54 have a zero width G by forming the aperture 35 by stamping, in which case the "reverse 44" is formed by shearing the baffle from the front bulkhead 4. However, it is generally expensive to manufacture. Tool and laser cutting 1:1 should be changed (eg 'different orifice size, shape or pattern'). The method can form a gap as small as 0.020 。. - General:: with:: In the middle, the circular orifice has a diameter of two-leaf. Guidance life: The larger the total area in the separator, the more the gas passes through the plate. ^ The smaller holes allow the gas to be more evenly distributed in the second stage. The Y-hole should not be too small to be blocked by the condensed gas. The circular orifice (for example) has a diameter in the range from .25 to the i-leaf. 13 201239196 Figure 6 shows a rectangular hole in the front partition 60 A top plan view of the port 62. The rectangular aperture 62 has a gap 66 that defines the edge of the aperture 62 except that the gap 66 does not continuously completely surround the edge of the aperture 62. The fold line 64 attached to the barrier 68 (The fold line 64 has a length L) that completes the edge of the aperture 62. The fold line 64 is preferably disposed at the moment The longest dimension of the aperture 62. For example, in one embodiment, the rectangular aperture 62 has a dimension of one-half of a length multiplied by one inch, and the fold line 64 is preferably disposed on a side of the length of the inch. The size of the rectangular aperture can range from a length to a width ratio of 5 to 1. The advantages of the rectangular aperture include ease of manufacturability and between the baffle 68 and the front bulkhead 60 for a given aperture 62 size. Improved thermal conductivity (compared to a circular orifice). Since the length of the fold line 64 is larger on a rectangular orifice than on a circular orifice of comparable size, the thermal conductivity is improved. Figure 6 shows the front partition 70 A top plan view of the triangular aperture 62. The triangular aperture 72 can be shaped like an equilateral triangle or similar isosceles triangle. The polygonal aperture 72 has a gap 76, except that the gap % cannot continuously completely surround the triangular aperture 72. Outside the edge, the gap % defines the edge of the triangular aperture 72. The fold line 74 attached to the baffle 78 (the fold line 74 has a length L) completes the edge of the aperture 72. Again, the finger line 74 is preferably disposed in a triangular aperture The longest dimension of the mouth 74. The triangular aperture 72 is shaped like an equilateral triangle, and the fold line 74 can be located on the (four) edge of the aperture 72. However, if the triangular aperture 72 is shaped like an isosceles triangle, the fold line 74 can preferably be placed in the aperture. The shorter, non-equal length edges of the port 72 are symmetrical with respect to the remaining edges. _ 5 to Figure 7 show only example shapes of the apertures in the front bulkhead. Other shapes may be used. Port 14 201239196 42 may include apertures having any of these shapes, and aperture 42 may comprise a mixture of different shapes. Figure 8A shows a low temperature fruit 8 having a plurality of apertures 82 before a plurality of apertures 82 Another specific example. In this particular example, the baffles 84 are configured such that the baffles are directed toward the process chamber 13 and away from the second stage array 34. Similar to Figure 2, aperture 82 can include apertures of any shape' and can include a mixture of different shapes. When there is more space on the side of the working chamber 13 than on the side of the second stage array 34, the front baffle 80 can be positioned with the baffle facing the processing chamber 13. Again, the baffles are oriented to direct the flow away from the second phase. Figure 8B shows another specific example of the spacer 85 prior to having a plurality of apertures 91. The front bulkhead 85 includes a plurality of layers 87, 89 that are stacked and joined together. Layer 87 includes aperture 91 and baffle 93 as described above with respect to Figures 3-7. Layer 89 includes aperture 91' but does not include baffle 93. The figure shows only two layers 87, 89. However, the 'front baffle may be formed from more than two layers. The plurality of layers can be joined together by any means including, but not limited to, welding, welding, rivets, screws, bolts, and adhesives. Figure 9 shows a specific example of a cryopump 9 having a large-area top plate 9 that can be positioned over the uppermost baffle of the second stage array 34 of the baffle or as a second alternative to the baffle as shown The uppermost partition of the stage array ^. The large-area top plate 90 results in a gap between itself and the radiation shield% (1) 剩余 the remaining gap of the spacer array 34 (4) the gap 94 between the light-shielding shields is small. For a given amount of the pumped π-type gas, the large-area top: 90 reduces the thickness of the condensed gas, which results in a smaller temperature difference across the thickness of the condensate during pumping and also reduces the duty cycle to return to the baseline temperature. The amount of time required between 201239196, as described in τ, ^ large-area top plate 9Q will also allow more π-type gas to be pumped, because the total volume of condensate v for the same thickness will be larger due to larger The area increases. The large-area top plate 90 reduces the amount of the first-type gas that reaches the remaining separator of the separator array 34 and the adsorbent material (not shown) on the lower side of the remaining separator. The figure shows a side view cross section of the circular large-area top plate 9 of the second-stage array and the condensed gas layer 1〇2 built thereon. The condensed gases consist of a condensed type 11 gas. As noted above, the particular gas from the process chamber 13 passes through the front baffle and condenses on the top plate 9 of the second stage array. The milk is condensed into a layer having a thickness [1], and the gases have a thermal conductivity κ. As described above, the large-area top plate 9 is maintained at an extremely low temperature L. The temperature at the surface of the condensed gas 102 will be a different temperature than I. When the working chamber is interposed and no additional gas is added to the cryopump, L will eventually fall to equal (or very close to) Τιβ. However, when new gas is introduced from the working chamber into the cryopump and in the condensed gas When condensing above 1〇2, the difference between D2 and D1 is the thickness of condensed gas 1〇2 (the thermal conductivity of condensed gas 102 & and the condensed incoming gas on plate 9〇) The function of temperature and arrival rate. The thicker the condensed gas layer 102, the longer it takes for I to return to Tl after the working cycle of the processing chamber 13. If the temperature is above the threshold temperature, the low temperature pump cannot effectively work from the working chamber. The gas is pumped, and the longer the temperature is above the threshold temperature, the longer the period of time when the working chamber 不可13 is not usable. Therefore, the time required for τ2 to fall below the threshold level after receiving gas from the working chamber The amount is a factor used to determine when to regenerate the cryopump. Minimizing the thickness of the condensed gas 102 is therefore beneficial for the time between the most degraded regeneration cycles, 16 201239196. Figure 11A and Figure 11B illustrate how the large-area top plate 9〇 Minimize the thickness of the condensed gas 102 First, for a cylindrical plate such as the one shown in Figure nA and Figure UB, please note that the condensed gas 1〇2 forms a substantially cylindrical volume (ignoring the slightly rounded side and cladding to the large diameter top plate 9〇) Condensed gas on the opposite side. Figure 11A shows a side view cross section of a circular top plate ιι having a small diameter Di. The plate 11 is representative of the top baffle from the baffle array 34. For simplicity, neglect An angled edge is shown in the array of partitions 34. The top plate 11 has a condensed gas layer 112 thereon. The condensed gas us has a volume V and is cylindrical. Figure 11B shows a large circular area having a large diameter. A side view cross section of the top plate 114, where h is greater than. The large area top plate 114 has a condensed gas layer 116 thereon<> condensed gas (μ has the same volume v as the condensed gas 112 on the plate 110. However, condensed gas The thickness t2 of U6 is smaller than the thickness h of the condensed gas 2 on the plate 11 of Fig. 11A. The volume of the cylinder is redundant d2/4 times the thickness t. Therefore, increasing the diameter of the plate from D1 to A means the same Volume v of condensed gas and H6 will The thickness is reduced from ti to t2. For the same volume of frost, the large-area top plate 114 can therefore return to Τι from A faster than the plate 110. Again, the large-area top plate 114 can be reduced to I in an acceptable amount of time. And the condensed gas accumulated on the large-area top plate is more than the condensed gas that can be accumulated in the reverse 110. Also, because for a given volume of the condensed gas 116, the difference between the Τ丨 and the butyl 2 is small, so the large-area top plate 114 The temperature τ can be higher than the temperature T of the small top plate 110 while still maintaining the acceptable temperature h of the condensed gas 丨16. Returning to Fig. 9 the large-area top plate 90 is also prevented by capturing more n-type gas 17 201239196 The π-type gases reach the remaining separators in the separator array 34 and some or all of the adsorbent material (not shown) of the remaining separators to improve the low temperature system. The third gas will condense on the adsorbent material, but this condensation reduces the ability of the adsorbent material to adsorb the m-type gas. The π-type gas is preferably condensed on the large-area top plate 9 to hold the adsorbent material for the m-type gas. The large-area top plate 90 provides a gap 92 between the edge of the large-area top plate 9A and the light-shielding shield 36 that is smaller than the gap 94 between the remaining partition of the baffle array 34 and the radiation shield 36. The smaller gap % reduces the amount of the π-type gas passing between the large-area top plate 9 〇 and the radiation shield 36. However, the smaller gap also slows the movement of the Type III gas of the adsorbent material on the remaining separators that reach the separator array 34, thereby reducing the pumping speed of their gases. Moreover, the large surface area of the large-area top plate 90 allows the large-area top plate 9" to be easily affected by radiation from the working chamber. Increasing the large-area top plate 9 〇 light exposure increases the large-area top plate 9 〇 so the second stage of the thermal load is also the same. In one embodiment of the circular cryopump according to the present invention, the diameter 〇2 of the circular large-area top plate 90 is 6.5 忖 and the diameter D of the remaining partition plates in the separator array 34 is 5.28 吋. In one of the tests of this construction, it was found that the pumping speed of the first industrial work type gas was reduced by about 12%. However, other diameters are also possible. The circular large-area top plate 90 can have any diameter that is greater than the straightness of the baffle array 34 while leaving a gap between the plate and the radiation shield 36 to provide sufficient pumping speed for the Type III gas. The baffle array 34 typically has a diameter of about 7% of the diameter of the radiation shield 36. The large-area top plate 9 can have a non-circular cryopump with a diameter of about 7〇% between the diameter of the radiation shield 36, and the large top plate has 50% and 95% of the cross-sectional area of the cross-sectional 18 201239196 of the wheel shield. The cross-sectional area between %. Preferably, the area will be (four) to 9 〇% of the opening area before the light-shielding shield. Top plate: The adsorbent is supported on its bottom surface. Figure U is a graph showing the results of various A J measurements for a large-area top plate that is not used for a particular circular cryopump. The sinogram shows the surface temperature of the condensed gas ("Cream") as the volume of the condensed gas increases. For the test, the characteristic temperature of the jin is low, and the threshold temperature of the surface temperature of the condensed gas is 27 K. The temperature will be unacceptable and the regenerative pump will be needed. The graph shows that a larger area of the top plate holds a larger volume of condensed gas while maintaining the temperature below the threshold temperature of 12 。. For example, a circular large-area top plate i having a diameter of 5 inches can accumulate about 23 cubic feet of condensed gas before the surface temperature of the condensed gas exceeds the threshold temperature by 12 Torr. In a further example, a circular large-area top plate 2 having a diameter of 5.5 可 can accumulate approximately 2.7 cubic feet of condensed gas before the surface temperature of the condensed gas exceeds the threshold temperature 120. In still another example, the circular large-area top plate 3 having a diameter of 6.0 可 can accumulate a condensed gas of about 3. 丨 cubic 〇 before the surface temperature of the condensed gas exceeds the threshold temperature by 12 〇. In the fourth example, a circular large-area top plate 4 having a diameter of 6.5 Å can accumulate approximately 2.6 cubic pairs of condensed gas before the surface temperature of the condensed gas exceeds the threshold temperature by 12 Torr. Figure 13 shows both a front bulkhead 40 (such as the one previously described in Figures 3 through 8) and a large-area top panel 90 (such as the one described in Figures 9-11). Side view cross section of low temperature fruit 1.0. The combination of front partition 40 and large area top 90 is beneficial. The front bulkhead 40 allows for the passage of the second stage array 34 and the top plate 90 of the partition from the previous processing to the 13th. The reduced radiation reduces the degree of the spacer array 'and the reduction of the ocean & the separator/top plate 9 closest to the front spacer 4〇. As explained above, the large-area top plate 90 is capable of capturing a large volume of condensation. Gas and maintain acceptable temperatures. Fig. 14 is a graph showing the advantages of a low pump 1 并 having both a front bulkhead 4〇 and a large-area top plate. Figure 14 shows the results of a vacuum test in which the cryopump can be maintained at various flow rates based on the total volume of the pumped volume. The low temperature pump used in the shellfish type shall not exceed the threshold pressure of 1 X 1 〇 _6 Torr. If the cryopump cannot maintain the pressure below the threshold pressure 122, the low temperature pump must be regenerated. The chart shows that a standard cryopump (such as the cryopump shown in Figure i) that is pumping a gas at a rate of 1 〇〇 standard centimeters per minute (seem) is unable to maintain the pressure at the threshold pressure i22 The following may be convulsed approximately 1750 liters. In contrast, a standard cryopump pumping at a rate of 23 〇 sccm 126 can only draw about 42 liters of gas before it can maintain the pressure below a predetermined pressure 122. The cryopump 1〇 (which is being pumped at 23〇seem 128) with both the baffle 40 and the large-area top plate 9 can be twitched beyond ^00 before it can maintain the pressure below the threshold pressure 122. liter. A cryopump having only one of the front baffle 4〇 and the large-area top plate 90 can exhibit results between two rates 126 and 128 as illustrated by 23 〇 sccm. 15A and 15B illustrate still another embodiment of the present invention using a large-area top plate 9''. In this particular example, the front array includes concentric rings 13 that are supported on rods 132 and 134 that are coupled to the walls of the radiation shield. Although these 20 201239196: the heart ring may include the apex as illustrated in the figure, in order to increase the speed, each -% is a frustoconical ring that is angled in only one direction. A preferred angle is 10. To 60. In the range, but better at 35. To ^. In the scope. The choice of angle is the trade-off between speed and the light thermal load on the second stage. Preferably, the outer diameter of each ring is about the same as or exactly the inner diameter of the next larger ring. Although the loops are shown as being supported by the side walls of the light-shielding shield, the loops may be supported by longitudinally extending struts that extend to the base of the radiation shield. In other embodiments, as described above, the low-pump pump having the front baffle array and/or the top plate may be non-circular in shape. Examples of such non-circular cryogenic pumps are described in U.S. Patent No. 6,155, G59, the disclosure of which is incorporated herein in its entirety. For rectangular low hot springs, the large top plate preferably covers 50% to 98°/ of the cross-sectional area of the radiation shield. . In other specific embodiments, as described above, the cryopump having the front baffle array and/or the large top plate can be a field cryogenic system or an accessory system. Examples of such on-site cryopumps and associated cryopumps are described in the Patent Cooperation Treaty Application No. pcT/US2〇〇9/〇65i68, the contents of which are incorporated by reference in its entirety. The teachings of all patents, published applications and references cited herein are hereby incorporated by reference in their entirety. While the present invention has been particularly shown and described with reference to the embodiments of the present invention, it will be understood by those skilled in the art that the form and details may be made without departing from the scope of the invention as covered by the appended claims. Various changes. BRIEF DESCRIPTION OF THE DRAWINGS 21 201239196 FIG. 1A is a side cross-sectional view of a prior art cryopump; FIG. 1B is a side cross-sectional view of another prior art cryogenic system; FIG. 2 is a cryopump having a specific example of a front baffle Figure 3A is a plan view of a specific example of the spacer before having a circular aperture; Figure 3B is a side cross-sectional view of a specific example of the prior spacer shown in Figure 3A; Figure 3C is a rectangular aperture FIG. 4 is a perspective view of the aperture and the baffle in the specific example of the prior spacer shown in FIGS. 3A and 3B; FIG. 5 is FIG. 3, FIG. 3B and FIG. A top view of the aperture in the front bulkhead is shown; Figure 6 is a top plan view of the rectangular aperture in the front bulkhead; Figure 7 is a top plan view of the triangular aperture in the front bulkhead; Figure 8A is a top view of the front bulkhead; A side view cross-section of a cryopump of a specific example; FIG. 8B is a side cross-sectional view of the front bulkhead; FIG. 9 is a side cross-sectional view of a cryopump having another specific example of a large-area top plate; Side view cross section of the large-area roof shown in Figure 11A is a side cross-sectional view of the second stage top plate; Figure 11B is a side view cross section of the second stage large area top plate; Figure 12 is a chart showing the condensed gas capacity of various large area top plates having different diameters; 201239196 Figure 13 is a side cross-sectional view of a cryopump having a specific example of a front baffle incorporating a specific example of a large-area top plate; Figure 14 is a graph showing the pumping ability of various cryopump constructions; Figure 1 5 A has Side view cross-section of the cryopump of the array and the large-area top plate before the concentric rings; and Figure 15B is a plan view of the array prior to Figure 15A. [Main component symbol description] 23